CGExprAgg.cpp revision 201361
1193326Sed//===--- CGExprAgg.cpp - Emit LLVM Code from Aggregate Expressions --------===// 2193326Sed// 3193326Sed// The LLVM Compiler Infrastructure 4193326Sed// 5193326Sed// This file is distributed under the University of Illinois Open Source 6193326Sed// License. See LICENSE.TXT for details. 7193326Sed// 8193326Sed//===----------------------------------------------------------------------===// 9193326Sed// 10193326Sed// This contains code to emit Aggregate Expr nodes as LLVM code. 11193326Sed// 12193326Sed//===----------------------------------------------------------------------===// 13193326Sed 14193326Sed#include "CodeGenFunction.h" 15193326Sed#include "CodeGenModule.h" 16198092Srdivacky#include "CGObjCRuntime.h" 17193326Sed#include "clang/AST/ASTContext.h" 18193326Sed#include "clang/AST/DeclCXX.h" 19193326Sed#include "clang/AST/StmtVisitor.h" 20193326Sed#include "llvm/Constants.h" 21193326Sed#include "llvm/Function.h" 22193326Sed#include "llvm/GlobalVariable.h" 23193326Sed#include "llvm/Intrinsics.h" 24193326Sedusing namespace clang; 25193326Sedusing namespace CodeGen; 26193326Sed 27193326Sed//===----------------------------------------------------------------------===// 28193326Sed// Aggregate Expression Emitter 29193326Sed//===----------------------------------------------------------------------===// 30193326Sed 31193326Sednamespace { 32199990Srdivackyclass AggExprEmitter : public StmtVisitor<AggExprEmitter> { 33193326Sed CodeGenFunction &CGF; 34193326Sed CGBuilderTy &Builder; 35193326Sed llvm::Value *DestPtr; 36193326Sed bool VolatileDest; 37193326Sed bool IgnoreResult; 38198092Srdivacky bool IsInitializer; 39198092Srdivacky bool RequiresGCollection; 40193326Sedpublic: 41193326Sed AggExprEmitter(CodeGenFunction &cgf, llvm::Value *destPtr, bool v, 42198092Srdivacky bool ignore, bool isinit, bool requiresGCollection) 43193326Sed : CGF(cgf), Builder(CGF.Builder), 44198092Srdivacky DestPtr(destPtr), VolatileDest(v), IgnoreResult(ignore), 45198092Srdivacky IsInitializer(isinit), RequiresGCollection(requiresGCollection) { 46193326Sed } 47193326Sed 48193326Sed //===--------------------------------------------------------------------===// 49193326Sed // Utilities 50193326Sed //===--------------------------------------------------------------------===// 51193326Sed 52193326Sed /// EmitAggLoadOfLValue - Given an expression with aggregate type that 53193326Sed /// represents a value lvalue, this method emits the address of the lvalue, 54193326Sed /// then loads the result into DestPtr. 55193326Sed void EmitAggLoadOfLValue(const Expr *E); 56193326Sed 57193326Sed /// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 58193326Sed void EmitFinalDestCopy(const Expr *E, LValue Src, bool Ignore = false); 59193326Sed void EmitFinalDestCopy(const Expr *E, RValue Src, bool Ignore = false); 60193326Sed 61193326Sed //===--------------------------------------------------------------------===// 62193326Sed // Visitor Methods 63193326Sed //===--------------------------------------------------------------------===// 64198092Srdivacky 65193326Sed void VisitStmt(Stmt *S) { 66193326Sed CGF.ErrorUnsupported(S, "aggregate expression"); 67193326Sed } 68193326Sed void VisitParenExpr(ParenExpr *PE) { Visit(PE->getSubExpr()); } 69193326Sed void VisitUnaryExtension(UnaryOperator *E) { Visit(E->getSubExpr()); } 70193326Sed 71193326Sed // l-values. 72193326Sed void VisitDeclRefExpr(DeclRefExpr *DRE) { EmitAggLoadOfLValue(DRE); } 73193326Sed void VisitMemberExpr(MemberExpr *ME) { EmitAggLoadOfLValue(ME); } 74193326Sed void VisitUnaryDeref(UnaryOperator *E) { EmitAggLoadOfLValue(E); } 75193326Sed void VisitStringLiteral(StringLiteral *E) { EmitAggLoadOfLValue(E); } 76193326Sed void VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 77198092Srdivacky EmitAggLoadOfLValue(E); 78193326Sed } 79193326Sed void VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 80193326Sed EmitAggLoadOfLValue(E); 81193326Sed } 82193326Sed void VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 83198092Srdivacky EmitAggLoadOfLValue(E); 84193326Sed } 85193326Sed void VisitPredefinedExpr(const PredefinedExpr *E) { 86198092Srdivacky EmitAggLoadOfLValue(E); 87193326Sed } 88198092Srdivacky 89193326Sed // Operators. 90198092Srdivacky void VisitCastExpr(CastExpr *E); 91193326Sed void VisitCallExpr(const CallExpr *E); 92193326Sed void VisitStmtExpr(const StmtExpr *E); 93193326Sed void VisitBinaryOperator(const BinaryOperator *BO); 94198398Srdivacky void VisitPointerToDataMemberBinaryOperator(const BinaryOperator *BO); 95193326Sed void VisitBinAssign(const BinaryOperator *E); 96193326Sed void VisitBinComma(const BinaryOperator *E); 97198092Srdivacky void VisitUnaryAddrOf(const UnaryOperator *E); 98193326Sed 99193326Sed void VisitObjCMessageExpr(ObjCMessageExpr *E); 100193326Sed void VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 101193326Sed EmitAggLoadOfLValue(E); 102193326Sed } 103193326Sed void VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E); 104198092Srdivacky void VisitObjCImplicitSetterGetterRefExpr(ObjCImplicitSetterGetterRefExpr *E); 105198092Srdivacky 106193326Sed void VisitConditionalOperator(const ConditionalOperator *CO); 107198092Srdivacky void VisitChooseExpr(const ChooseExpr *CE); 108193326Sed void VisitInitListExpr(InitListExpr *E); 109201361Srdivacky void VisitImplicitValueInitExpr(ImplicitValueInitExpr *E); 110193326Sed void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 111193326Sed Visit(DAE->getExpr()); 112193326Sed } 113193326Sed void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E); 114193326Sed void VisitCXXConstructExpr(const CXXConstructExpr *E); 115193326Sed void VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E); 116198398Srdivacky void VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E); 117199482Srdivacky void VisitCXXTypeidExpr(CXXTypeidExpr *E) { EmitAggLoadOfLValue(E); } 118193326Sed 119193326Sed void VisitVAArgExpr(VAArgExpr *E); 120193326Sed 121193326Sed void EmitInitializationToLValue(Expr *E, LValue Address); 122193326Sed void EmitNullInitializationToLValue(LValue Address, QualType T); 123193326Sed // case Expr::ChooseExprClass: 124200583Srdivacky void VisitCXXThrowExpr(const CXXThrowExpr *E) { CGF.EmitCXXThrowExpr(E); } 125193326Sed}; 126193326Sed} // end anonymous namespace. 127193326Sed 128193326Sed//===----------------------------------------------------------------------===// 129193326Sed// Utilities 130193326Sed//===----------------------------------------------------------------------===// 131193326Sed 132193326Sed/// EmitAggLoadOfLValue - Given an expression with aggregate type that 133193326Sed/// represents a value lvalue, this method emits the address of the lvalue, 134193326Sed/// then loads the result into DestPtr. 135193326Sedvoid AggExprEmitter::EmitAggLoadOfLValue(const Expr *E) { 136193326Sed LValue LV = CGF.EmitLValue(E); 137193326Sed EmitFinalDestCopy(E, LV); 138193326Sed} 139193326Sed 140193326Sed/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 141193326Sedvoid AggExprEmitter::EmitFinalDestCopy(const Expr *E, RValue Src, bool Ignore) { 142193326Sed assert(Src.isAggregate() && "value must be aggregate value!"); 143193326Sed 144193326Sed // If the result is ignored, don't copy from the value. 145193326Sed if (DestPtr == 0) { 146193326Sed if (!Src.isVolatileQualified() || (IgnoreResult && Ignore)) 147193326Sed return; 148193326Sed // If the source is volatile, we must read from it; to do that, we need 149193326Sed // some place to put it. 150193326Sed DestPtr = CGF.CreateTempAlloca(CGF.ConvertType(E->getType()), "agg.tmp"); 151193326Sed } 152193326Sed 153198092Srdivacky if (RequiresGCollection) { 154198092Srdivacky CGF.CGM.getObjCRuntime().EmitGCMemmoveCollectable(CGF, 155198092Srdivacky DestPtr, Src.getAggregateAddr(), 156198092Srdivacky E->getType()); 157198092Srdivacky return; 158198092Srdivacky } 159193326Sed // If the result of the assignment is used, copy the LHS there also. 160193326Sed // FIXME: Pass VolatileDest as well. I think we also need to merge volatile 161193326Sed // from the source as well, as we can't eliminate it if either operand 162193326Sed // is volatile, unless copy has volatile for both source and destination.. 163193326Sed CGF.EmitAggregateCopy(DestPtr, Src.getAggregateAddr(), E->getType(), 164193326Sed VolatileDest|Src.isVolatileQualified()); 165193326Sed} 166193326Sed 167193326Sed/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 168193326Sedvoid AggExprEmitter::EmitFinalDestCopy(const Expr *E, LValue Src, bool Ignore) { 169193326Sed assert(Src.isSimple() && "Can't have aggregate bitfield, vector, etc"); 170193326Sed 171193326Sed EmitFinalDestCopy(E, RValue::getAggregate(Src.getAddress(), 172193326Sed Src.isVolatileQualified()), 173193326Sed Ignore); 174193326Sed} 175193326Sed 176193326Sed//===----------------------------------------------------------------------===// 177193326Sed// Visitor Methods 178193326Sed//===----------------------------------------------------------------------===// 179193326Sed 180198092Srdivackyvoid AggExprEmitter::VisitCastExpr(CastExpr *E) { 181198092Srdivacky switch (E->getCastKind()) { 182198092Srdivacky default: assert(0 && "Unhandled cast kind!"); 183198092Srdivacky 184198092Srdivacky case CastExpr::CK_ToUnion: { 185198092Srdivacky // GCC union extension 186193401Sed QualType PtrTy = 187198092Srdivacky CGF.getContext().getPointerType(E->getSubExpr()->getType()); 188193401Sed llvm::Value *CastPtr = Builder.CreateBitCast(DestPtr, 189193401Sed CGF.ConvertType(PtrTy)); 190198092Srdivacky EmitInitializationToLValue(E->getSubExpr(), 191198092Srdivacky LValue::MakeAddr(CastPtr, Qualifiers())); 192198092Srdivacky break; 193193326Sed } 194193326Sed 195198092Srdivacky // FIXME: Remove the CK_Unknown check here. 196198092Srdivacky case CastExpr::CK_Unknown: 197198092Srdivacky case CastExpr::CK_NoOp: 198198092Srdivacky case CastExpr::CK_UserDefinedConversion: 199198092Srdivacky case CastExpr::CK_ConstructorConversion: 200198092Srdivacky assert(CGF.getContext().hasSameUnqualifiedType(E->getSubExpr()->getType(), 201198092Srdivacky E->getType()) && 202198092Srdivacky "Implicit cast types must be compatible"); 203198092Srdivacky Visit(E->getSubExpr()); 204198092Srdivacky break; 205193326Sed 206198092Srdivacky case CastExpr::CK_NullToMemberPointer: { 207198092Srdivacky const llvm::Type *PtrDiffTy = 208198092Srdivacky CGF.ConvertType(CGF.getContext().getPointerDiffType()); 209198092Srdivacky 210198092Srdivacky llvm::Value *NullValue = llvm::Constant::getNullValue(PtrDiffTy); 211198092Srdivacky llvm::Value *Ptr = Builder.CreateStructGEP(DestPtr, 0, "ptr"); 212198092Srdivacky Builder.CreateStore(NullValue, Ptr, VolatileDest); 213198092Srdivacky 214198092Srdivacky llvm::Value *Adj = Builder.CreateStructGEP(DestPtr, 1, "adj"); 215198092Srdivacky Builder.CreateStore(NullValue, Adj, VolatileDest); 216198092Srdivacky 217198092Srdivacky break; 218198092Srdivacky } 219198092Srdivacky 220198398Srdivacky case CastExpr::CK_BitCast: { 221198398Srdivacky // This must be a member function pointer cast. 222198398Srdivacky Visit(E->getSubExpr()); 223198398Srdivacky break; 224198398Srdivacky } 225198398Srdivacky 226199990Srdivacky case CastExpr::CK_DerivedToBaseMemberPointer: 227198092Srdivacky case CastExpr::CK_BaseToDerivedMemberPointer: { 228198092Srdivacky QualType SrcType = E->getSubExpr()->getType(); 229198092Srdivacky 230198092Srdivacky llvm::Value *Src = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(SrcType), 231198092Srdivacky "tmp"); 232198092Srdivacky CGF.EmitAggExpr(E->getSubExpr(), Src, SrcType.isVolatileQualified()); 233198092Srdivacky 234198092Srdivacky llvm::Value *SrcPtr = Builder.CreateStructGEP(Src, 0, "src.ptr"); 235198092Srdivacky SrcPtr = Builder.CreateLoad(SrcPtr); 236198092Srdivacky 237198092Srdivacky llvm::Value *SrcAdj = Builder.CreateStructGEP(Src, 1, "src.adj"); 238198092Srdivacky SrcAdj = Builder.CreateLoad(SrcAdj); 239198092Srdivacky 240198092Srdivacky llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr"); 241198092Srdivacky Builder.CreateStore(SrcPtr, DstPtr, VolatileDest); 242198092Srdivacky 243198092Srdivacky llvm::Value *DstAdj = Builder.CreateStructGEP(DestPtr, 1, "dst.adj"); 244198092Srdivacky 245198092Srdivacky // Now See if we need to update the adjustment. 246199990Srdivacky const CXXRecordDecl *BaseDecl = 247198092Srdivacky cast<CXXRecordDecl>(SrcType->getAs<MemberPointerType>()-> 248198092Srdivacky getClass()->getAs<RecordType>()->getDecl()); 249199990Srdivacky const CXXRecordDecl *DerivedDecl = 250198092Srdivacky cast<CXXRecordDecl>(E->getType()->getAs<MemberPointerType>()-> 251198092Srdivacky getClass()->getAs<RecordType>()->getDecl()); 252199990Srdivacky if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 253199990Srdivacky std::swap(DerivedDecl, BaseDecl); 254199990Srdivacky 255199990Srdivacky llvm::Constant *Adj = CGF.CGM.GetCXXBaseClassOffset(DerivedDecl, BaseDecl); 256199990Srdivacky if (Adj) { 257199990Srdivacky if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 258199990Srdivacky SrcAdj = Builder.CreateSub(SrcAdj, Adj, "adj"); 259199990Srdivacky else 260199990Srdivacky SrcAdj = Builder.CreateAdd(SrcAdj, Adj, "adj"); 261199990Srdivacky } 262198092Srdivacky 263198092Srdivacky Builder.CreateStore(SrcAdj, DstAdj, VolatileDest); 264198092Srdivacky break; 265198092Srdivacky } 266198092Srdivacky } 267193326Sed} 268193326Sed 269193326Sedvoid AggExprEmitter::VisitCallExpr(const CallExpr *E) { 270193326Sed if (E->getCallReturnType()->isReferenceType()) { 271193326Sed EmitAggLoadOfLValue(E); 272193326Sed return; 273193326Sed } 274198092Srdivacky 275201361Srdivacky // If the struct doesn't require GC, we can just pass the destination 276201361Srdivacky // directly to EmitCall. 277201361Srdivacky if (!RequiresGCollection) { 278201361Srdivacky CGF.EmitCallExpr(E, ReturnValueSlot(DestPtr, VolatileDest)); 279201361Srdivacky return; 280201361Srdivacky } 281201361Srdivacky 282193326Sed RValue RV = CGF.EmitCallExpr(E); 283193326Sed EmitFinalDestCopy(E, RV); 284193326Sed} 285193326Sed 286193326Sedvoid AggExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) { 287193326Sed RValue RV = CGF.EmitObjCMessageExpr(E); 288193326Sed EmitFinalDestCopy(E, RV); 289193326Sed} 290193326Sed 291193326Sedvoid AggExprEmitter::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 292193326Sed RValue RV = CGF.EmitObjCPropertyGet(E); 293193326Sed EmitFinalDestCopy(E, RV); 294193326Sed} 295193326Sed 296198092Srdivackyvoid AggExprEmitter::VisitObjCImplicitSetterGetterRefExpr( 297198092Srdivacky ObjCImplicitSetterGetterRefExpr *E) { 298193326Sed RValue RV = CGF.EmitObjCPropertyGet(E); 299193326Sed EmitFinalDestCopy(E, RV); 300193326Sed} 301193326Sed 302193326Sedvoid AggExprEmitter::VisitBinComma(const BinaryOperator *E) { 303193326Sed CGF.EmitAnyExpr(E->getLHS(), 0, false, true); 304198092Srdivacky CGF.EmitAggExpr(E->getRHS(), DestPtr, VolatileDest, 305198092Srdivacky /*IgnoreResult=*/false, IsInitializer); 306193326Sed} 307193326Sed 308198092Srdivackyvoid AggExprEmitter::VisitUnaryAddrOf(const UnaryOperator *E) { 309198092Srdivacky // We have a member function pointer. 310198092Srdivacky const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>(); 311198398Srdivacky (void) MPT; 312198092Srdivacky assert(MPT->getPointeeType()->isFunctionProtoType() && 313198092Srdivacky "Unexpected member pointer type!"); 314198092Srdivacky 315198893Srdivacky const DeclRefExpr *DRE = cast<DeclRefExpr>(E->getSubExpr()); 316198092Srdivacky const CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 317198092Srdivacky 318198092Srdivacky const llvm::Type *PtrDiffTy = 319198092Srdivacky CGF.ConvertType(CGF.getContext().getPointerDiffType()); 320198092Srdivacky 321198092Srdivacky llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr"); 322198092Srdivacky llvm::Value *FuncPtr; 323198092Srdivacky 324198092Srdivacky if (MD->isVirtual()) { 325198092Srdivacky int64_t Index = 326198092Srdivacky CGF.CGM.getVtableInfo().getMethodVtableIndex(MD); 327198092Srdivacky 328198092Srdivacky FuncPtr = llvm::ConstantInt::get(PtrDiffTy, Index + 1); 329198092Srdivacky } else { 330198092Srdivacky FuncPtr = llvm::ConstantExpr::getPtrToInt(CGF.CGM.GetAddrOfFunction(MD), 331198092Srdivacky PtrDiffTy); 332198092Srdivacky } 333198092Srdivacky Builder.CreateStore(FuncPtr, DstPtr, VolatileDest); 334198092Srdivacky 335198092Srdivacky llvm::Value *AdjPtr = Builder.CreateStructGEP(DestPtr, 1, "dst.adj"); 336198092Srdivacky 337198092Srdivacky // The adjustment will always be 0. 338198092Srdivacky Builder.CreateStore(llvm::ConstantInt::get(PtrDiffTy, 0), AdjPtr, 339198092Srdivacky VolatileDest); 340198092Srdivacky} 341198092Srdivacky 342193326Sedvoid AggExprEmitter::VisitStmtExpr(const StmtExpr *E) { 343193326Sed CGF.EmitCompoundStmt(*E->getSubStmt(), true, DestPtr, VolatileDest); 344193326Sed} 345193326Sed 346193326Sedvoid AggExprEmitter::VisitBinaryOperator(const BinaryOperator *E) { 347198893Srdivacky if (E->getOpcode() == BinaryOperator::PtrMemD || 348198893Srdivacky E->getOpcode() == BinaryOperator::PtrMemI) 349198398Srdivacky VisitPointerToDataMemberBinaryOperator(E); 350198398Srdivacky else 351198398Srdivacky CGF.ErrorUnsupported(E, "aggregate binary expression"); 352193326Sed} 353193326Sed 354198398Srdivackyvoid AggExprEmitter::VisitPointerToDataMemberBinaryOperator( 355198398Srdivacky const BinaryOperator *E) { 356198398Srdivacky LValue LV = CGF.EmitPointerToDataMemberBinaryExpr(E); 357198398Srdivacky EmitFinalDestCopy(E, LV); 358198398Srdivacky} 359198398Srdivacky 360193326Sedvoid AggExprEmitter::VisitBinAssign(const BinaryOperator *E) { 361193326Sed // For an assignment to work, the value on the right has 362193326Sed // to be compatible with the value on the left. 363193326Sed assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(), 364193326Sed E->getRHS()->getType()) 365193326Sed && "Invalid assignment"); 366193326Sed LValue LHS = CGF.EmitLValue(E->getLHS()); 367193326Sed 368193326Sed // We have to special case property setters, otherwise we must have 369193326Sed // a simple lvalue (no aggregates inside vectors, bitfields). 370193326Sed if (LHS.isPropertyRef()) { 371193326Sed llvm::Value *AggLoc = DestPtr; 372193326Sed if (!AggLoc) 373193326Sed AggLoc = CGF.CreateTempAlloca(CGF.ConvertType(E->getRHS()->getType())); 374193326Sed CGF.EmitAggExpr(E->getRHS(), AggLoc, VolatileDest); 375198092Srdivacky CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), 376193326Sed RValue::getAggregate(AggLoc, VolatileDest)); 377198092Srdivacky } else if (LHS.isKVCRef()) { 378193326Sed llvm::Value *AggLoc = DestPtr; 379193326Sed if (!AggLoc) 380193326Sed AggLoc = CGF.CreateTempAlloca(CGF.ConvertType(E->getRHS()->getType())); 381193326Sed CGF.EmitAggExpr(E->getRHS(), AggLoc, VolatileDest); 382198092Srdivacky CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), 383193326Sed RValue::getAggregate(AggLoc, VolatileDest)); 384193326Sed } else { 385198092Srdivacky bool RequiresGCollection = false; 386198092Srdivacky if (CGF.getContext().getLangOptions().NeXTRuntime) { 387198092Srdivacky QualType LHSTy = E->getLHS()->getType(); 388198092Srdivacky if (const RecordType *FDTTy = LHSTy.getTypePtr()->getAs<RecordType>()) 389198092Srdivacky RequiresGCollection = FDTTy->getDecl()->hasObjectMember(); 390198092Srdivacky } 391193326Sed // Codegen the RHS so that it stores directly into the LHS. 392198092Srdivacky CGF.EmitAggExpr(E->getRHS(), LHS.getAddress(), LHS.isVolatileQualified(), 393198092Srdivacky false, false, RequiresGCollection); 394193326Sed EmitFinalDestCopy(E, LHS, true); 395193326Sed } 396193326Sed} 397193326Sed 398193326Sedvoid AggExprEmitter::VisitConditionalOperator(const ConditionalOperator *E) { 399201361Srdivacky if (!E->getLHS()) { 400201361Srdivacky CGF.ErrorUnsupported(E, "conditional operator with missing LHS"); 401201361Srdivacky return; 402201361Srdivacky } 403201361Srdivacky 404193326Sed llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 405193326Sed llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 406193326Sed llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 407198092Srdivacky 408201361Srdivacky CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 409198092Srdivacky 410199990Srdivacky CGF.StartConditionalBranch(); 411193326Sed CGF.EmitBlock(LHSBlock); 412198092Srdivacky 413193326Sed // Handle the GNU extension for missing LHS. 414193326Sed assert(E->getLHS() && "Must have LHS for aggregate value"); 415193326Sed 416193326Sed Visit(E->getLHS()); 417199990Srdivacky CGF.FinishConditionalBranch(); 418193326Sed CGF.EmitBranch(ContBlock); 419198092Srdivacky 420199990Srdivacky CGF.StartConditionalBranch(); 421193326Sed CGF.EmitBlock(RHSBlock); 422198092Srdivacky 423193326Sed Visit(E->getRHS()); 424199990Srdivacky CGF.FinishConditionalBranch(); 425193326Sed CGF.EmitBranch(ContBlock); 426198092Srdivacky 427193326Sed CGF.EmitBlock(ContBlock); 428193326Sed} 429193326Sed 430198092Srdivackyvoid AggExprEmitter::VisitChooseExpr(const ChooseExpr *CE) { 431198092Srdivacky Visit(CE->getChosenSubExpr(CGF.getContext())); 432198092Srdivacky} 433198092Srdivacky 434193326Sedvoid AggExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 435193326Sed llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 436193326Sed llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 437193326Sed 438193326Sed if (!ArgPtr) { 439193326Sed CGF.ErrorUnsupported(VE, "aggregate va_arg expression"); 440193326Sed return; 441193326Sed } 442193326Sed 443198092Srdivacky EmitFinalDestCopy(VE, LValue::MakeAddr(ArgPtr, Qualifiers())); 444193326Sed} 445193326Sed 446193326Sedvoid AggExprEmitter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 447193326Sed llvm::Value *Val = DestPtr; 448198092Srdivacky 449193326Sed if (!Val) { 450193326Sed // Create a temporary variable. 451193326Sed Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 452193326Sed 453193326Sed // FIXME: volatile 454193326Sed CGF.EmitAggExpr(E->getSubExpr(), Val, false); 455198092Srdivacky } else 456193326Sed Visit(E->getSubExpr()); 457198092Srdivacky 458198092Srdivacky // Don't make this a live temporary if we're emitting an initializer expr. 459198092Srdivacky if (!IsInitializer) 460198092Srdivacky CGF.PushCXXTemporary(E->getTemporary(), Val); 461193326Sed} 462193326Sed 463193326Sedvoid 464193326SedAggExprEmitter::VisitCXXConstructExpr(const CXXConstructExpr *E) { 465193326Sed llvm::Value *Val = DestPtr; 466198092Srdivacky 467193326Sed if (!Val) { 468193326Sed // Create a temporary variable. 469193326Sed Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 470193326Sed } 471193326Sed 472201361Srdivacky if (E->requiresZeroInitialization()) 473201361Srdivacky EmitNullInitializationToLValue(LValue::MakeAddr(Val, 474201361Srdivacky // FIXME: Qualifiers()? 475201361Srdivacky E->getType().getQualifiers()), 476201361Srdivacky E->getType()); 477201361Srdivacky 478193326Sed CGF.EmitCXXConstructExpr(Val, E); 479193326Sed} 480193326Sed 481193326Sedvoid AggExprEmitter::VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 482201361Srdivacky llvm::Value *Val = DestPtr; 483201361Srdivacky 484201361Srdivacky if (!Val) { 485201361Srdivacky // Create a temporary variable. 486201361Srdivacky Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 487201361Srdivacky } 488201361Srdivacky CGF.EmitCXXExprWithTemporaries(E, Val, VolatileDest, IsInitializer); 489193326Sed} 490193326Sed 491198398Srdivackyvoid AggExprEmitter::VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) { 492201361Srdivacky llvm::Value *Val = DestPtr; 493201361Srdivacky 494201361Srdivacky if (!Val) { 495201361Srdivacky // Create a temporary variable. 496201361Srdivacky Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 497201361Srdivacky } 498201361Srdivacky LValue LV = LValue::MakeAddr(Val, Qualifiers()); 499201361Srdivacky EmitNullInitializationToLValue(LV, E->getType()); 500198398Srdivacky} 501198398Srdivacky 502201361Srdivackyvoid AggExprEmitter::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) { 503201361Srdivacky llvm::Value *Val = DestPtr; 504201361Srdivacky 505201361Srdivacky if (!Val) { 506201361Srdivacky // Create a temporary variable. 507201361Srdivacky Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 508201361Srdivacky } 509201361Srdivacky LValue LV = LValue::MakeAddr(Val, Qualifiers()); 510201361Srdivacky EmitNullInitializationToLValue(LV, E->getType()); 511201361Srdivacky} 512201361Srdivacky 513193326Sedvoid AggExprEmitter::EmitInitializationToLValue(Expr* E, LValue LV) { 514193326Sed // FIXME: Ignore result? 515193326Sed // FIXME: Are initializers affected by volatile? 516193326Sed if (isa<ImplicitValueInitExpr>(E)) { 517193326Sed EmitNullInitializationToLValue(LV, E->getType()); 518193326Sed } else if (E->getType()->isComplexType()) { 519193326Sed CGF.EmitComplexExprIntoAddr(E, LV.getAddress(), false); 520193326Sed } else if (CGF.hasAggregateLLVMType(E->getType())) { 521193326Sed CGF.EmitAnyExpr(E, LV.getAddress(), false); 522193326Sed } else { 523193326Sed CGF.EmitStoreThroughLValue(CGF.EmitAnyExpr(E), LV, E->getType()); 524193326Sed } 525193326Sed} 526193326Sed 527193326Sedvoid AggExprEmitter::EmitNullInitializationToLValue(LValue LV, QualType T) { 528193326Sed if (!CGF.hasAggregateLLVMType(T)) { 529193326Sed // For non-aggregates, we can store zero 530193326Sed llvm::Value *Null = llvm::Constant::getNullValue(CGF.ConvertType(T)); 531193326Sed CGF.EmitStoreThroughLValue(RValue::get(Null), LV, T); 532193326Sed } else { 533193326Sed // Otherwise, just memset the whole thing to zero. This is legal 534193326Sed // because in LLVM, all default initializers are guaranteed to have a 535193326Sed // bit pattern of all zeros. 536193326Sed // FIXME: That isn't true for member pointers! 537193326Sed // There's a potential optimization opportunity in combining 538193326Sed // memsets; that would be easy for arrays, but relatively 539193326Sed // difficult for structures with the current code. 540193326Sed CGF.EmitMemSetToZero(LV.getAddress(), T); 541193326Sed } 542193326Sed} 543193326Sed 544193326Sedvoid AggExprEmitter::VisitInitListExpr(InitListExpr *E) { 545193326Sed#if 0 546200583Srdivacky // FIXME: Assess perf here? Figure out what cases are worth optimizing here 547200583Srdivacky // (Length of globals? Chunks of zeroed-out space?). 548193326Sed // 549193326Sed // If we can, prefer a copy from a global; this is a lot less code for long 550193326Sed // globals, and it's easier for the current optimizers to analyze. 551200583Srdivacky if (llvm::Constant* C = CGF.CGM.EmitConstantExpr(E, E->getType(), &CGF)) { 552193326Sed llvm::GlobalVariable* GV = 553200583Srdivacky new llvm::GlobalVariable(CGF.CGM.getModule(), C->getType(), true, 554200583Srdivacky llvm::GlobalValue::InternalLinkage, C, ""); 555200583Srdivacky EmitFinalDestCopy(E, LValue::MakeAddr(GV, Qualifiers())); 556193326Sed return; 557193326Sed } 558193326Sed#endif 559193326Sed if (E->hadArrayRangeDesignator()) { 560193326Sed CGF.ErrorUnsupported(E, "GNU array range designator extension"); 561193326Sed } 562193326Sed 563193326Sed // Handle initialization of an array. 564193326Sed if (E->getType()->isArrayType()) { 565193326Sed const llvm::PointerType *APType = 566193326Sed cast<llvm::PointerType>(DestPtr->getType()); 567193326Sed const llvm::ArrayType *AType = 568193326Sed cast<llvm::ArrayType>(APType->getElementType()); 569198092Srdivacky 570193326Sed uint64_t NumInitElements = E->getNumInits(); 571193326Sed 572193326Sed if (E->getNumInits() > 0) { 573193326Sed QualType T1 = E->getType(); 574193326Sed QualType T2 = E->getInit(0)->getType(); 575193326Sed if (CGF.getContext().hasSameUnqualifiedType(T1, T2)) { 576193326Sed EmitAggLoadOfLValue(E->getInit(0)); 577193326Sed return; 578193326Sed } 579193326Sed } 580193326Sed 581193326Sed uint64_t NumArrayElements = AType->getNumElements(); 582193326Sed QualType ElementType = CGF.getContext().getCanonicalType(E->getType()); 583193326Sed ElementType = CGF.getContext().getAsArrayType(ElementType)->getElementType(); 584193326Sed 585198092Srdivacky // FIXME: were we intentionally ignoring address spaces and GC attributes? 586198092Srdivacky Qualifiers Quals = CGF.MakeQualifiers(ElementType); 587198092Srdivacky 588193326Sed for (uint64_t i = 0; i != NumArrayElements; ++i) { 589193326Sed llvm::Value *NextVal = Builder.CreateStructGEP(DestPtr, i, ".array"); 590193326Sed if (i < NumInitElements) 591193326Sed EmitInitializationToLValue(E->getInit(i), 592198092Srdivacky LValue::MakeAddr(NextVal, Quals)); 593193326Sed else 594198092Srdivacky EmitNullInitializationToLValue(LValue::MakeAddr(NextVal, Quals), 595193326Sed ElementType); 596193326Sed } 597193326Sed return; 598193326Sed } 599198092Srdivacky 600193326Sed assert(E->getType()->isRecordType() && "Only support structs/unions here!"); 601198092Srdivacky 602193326Sed // Do struct initialization; this code just sets each individual member 603193326Sed // to the approprate value. This makes bitfield support automatic; 604193326Sed // the disadvantage is that the generated code is more difficult for 605193326Sed // the optimizer, especially with bitfields. 606193326Sed unsigned NumInitElements = E->getNumInits(); 607198092Srdivacky RecordDecl *SD = E->getType()->getAs<RecordType>()->getDecl(); 608193326Sed unsigned CurInitVal = 0; 609193326Sed 610193326Sed if (E->getType()->isUnionType()) { 611193326Sed // Only initialize one field of a union. The field itself is 612193326Sed // specified by the initializer list. 613193326Sed if (!E->getInitializedFieldInUnion()) { 614193326Sed // Empty union; we have nothing to do. 615198092Srdivacky 616193326Sed#ifndef NDEBUG 617193326Sed // Make sure that it's really an empty and not a failure of 618193326Sed // semantic analysis. 619195341Sed for (RecordDecl::field_iterator Field = SD->field_begin(), 620195341Sed FieldEnd = SD->field_end(); 621193326Sed Field != FieldEnd; ++Field) 622193326Sed assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed"); 623193326Sed#endif 624193326Sed return; 625193326Sed } 626193326Sed 627193326Sed // FIXME: volatility 628193326Sed FieldDecl *Field = E->getInitializedFieldInUnion(); 629193326Sed LValue FieldLoc = CGF.EmitLValueForField(DestPtr, Field, true, 0); 630193326Sed 631193326Sed if (NumInitElements) { 632193326Sed // Store the initializer into the field 633193326Sed EmitInitializationToLValue(E->getInit(0), FieldLoc); 634193326Sed } else { 635193326Sed // Default-initialize to null 636193326Sed EmitNullInitializationToLValue(FieldLoc, Field->getType()); 637193326Sed } 638193326Sed 639193326Sed return; 640193326Sed } 641198092Srdivacky 642193326Sed // Here we iterate over the fields; this makes it simpler to both 643193326Sed // default-initialize fields and skip over unnamed fields. 644195341Sed for (RecordDecl::field_iterator Field = SD->field_begin(), 645195341Sed FieldEnd = SD->field_end(); 646193326Sed Field != FieldEnd; ++Field) { 647193326Sed // We're done once we hit the flexible array member 648193326Sed if (Field->getType()->isIncompleteArrayType()) 649193326Sed break; 650193326Sed 651193326Sed if (Field->isUnnamedBitfield()) 652193326Sed continue; 653193326Sed 654193326Sed // FIXME: volatility 655193326Sed LValue FieldLoc = CGF.EmitLValueForField(DestPtr, *Field, false, 0); 656193326Sed // We never generate write-barries for initialized fields. 657193326Sed LValue::SetObjCNonGC(FieldLoc, true); 658193326Sed if (CurInitVal < NumInitElements) { 659193326Sed // Store the initializer into the field 660193326Sed EmitInitializationToLValue(E->getInit(CurInitVal++), FieldLoc); 661193326Sed } else { 662193326Sed // We're out of initalizers; default-initialize to null 663193326Sed EmitNullInitializationToLValue(FieldLoc, Field->getType()); 664193326Sed } 665193326Sed } 666193326Sed} 667193326Sed 668193326Sed//===----------------------------------------------------------------------===// 669193326Sed// Entry Points into this File 670193326Sed//===----------------------------------------------------------------------===// 671193326Sed 672193326Sed/// EmitAggExpr - Emit the computation of the specified expression of aggregate 673193326Sed/// type. The result is computed into DestPtr. Note that if DestPtr is null, 674193326Sed/// the value of the aggregate expression is not needed. If VolatileDest is 675193326Sed/// true, DestPtr cannot be 0. 676193326Sedvoid CodeGenFunction::EmitAggExpr(const Expr *E, llvm::Value *DestPtr, 677198092Srdivacky bool VolatileDest, bool IgnoreResult, 678198092Srdivacky bool IsInitializer, 679198092Srdivacky bool RequiresGCollection) { 680193326Sed assert(E && hasAggregateLLVMType(E->getType()) && 681193326Sed "Invalid aggregate expression to emit"); 682193326Sed assert ((DestPtr != 0 || VolatileDest == false) 683193326Sed && "volatile aggregate can't be 0"); 684198092Srdivacky 685198092Srdivacky AggExprEmitter(*this, DestPtr, VolatileDest, IgnoreResult, IsInitializer, 686198092Srdivacky RequiresGCollection) 687193326Sed .Visit(const_cast<Expr*>(E)); 688193326Sed} 689193326Sed 690193326Sedvoid CodeGenFunction::EmitAggregateClear(llvm::Value *DestPtr, QualType Ty) { 691193326Sed assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex"); 692193326Sed 693193326Sed EmitMemSetToZero(DestPtr, Ty); 694193326Sed} 695193326Sed 696193326Sedvoid CodeGenFunction::EmitAggregateCopy(llvm::Value *DestPtr, 697193326Sed llvm::Value *SrcPtr, QualType Ty, 698193326Sed bool isVolatile) { 699193326Sed assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex"); 700198092Srdivacky 701193326Sed // Aggregate assignment turns into llvm.memcpy. This is almost valid per 702193326Sed // C99 6.5.16.1p3, which states "If the value being stored in an object is 703193326Sed // read from another object that overlaps in anyway the storage of the first 704193326Sed // object, then the overlap shall be exact and the two objects shall have 705193326Sed // qualified or unqualified versions of a compatible type." 706193326Sed // 707193326Sed // memcpy is not defined if the source and destination pointers are exactly 708193326Sed // equal, but other compilers do this optimization, and almost every memcpy 709193326Sed // implementation handles this case safely. If there is a libc that does not 710193326Sed // safely handle this, we can add a target hook. 711198092Srdivacky const llvm::Type *BP = llvm::Type::getInt8PtrTy(VMContext); 712193326Sed if (DestPtr->getType() != BP) 713193326Sed DestPtr = Builder.CreateBitCast(DestPtr, BP, "tmp"); 714193326Sed if (SrcPtr->getType() != BP) 715193326Sed SrcPtr = Builder.CreateBitCast(SrcPtr, BP, "tmp"); 716198092Srdivacky 717193326Sed // Get size and alignment info for this aggregate. 718193326Sed std::pair<uint64_t, unsigned> TypeInfo = getContext().getTypeInfo(Ty); 719198092Srdivacky 720193326Sed // FIXME: Handle variable sized types. 721198092Srdivacky const llvm::Type *IntPtr = 722198092Srdivacky llvm::IntegerType::get(VMContext, LLVMPointerWidth); 723198092Srdivacky 724193326Sed // FIXME: If we have a volatile struct, the optimizer can remove what might 725193326Sed // appear to be `extra' memory ops: 726193326Sed // 727193326Sed // volatile struct { int i; } a, b; 728193326Sed // 729193326Sed // int main() { 730193326Sed // a = b; 731193326Sed // a = b; 732193326Sed // } 733193326Sed // 734193326Sed // we need to use a differnt call here. We use isVolatile to indicate when 735193326Sed // either the source or the destination is volatile. 736193326Sed Builder.CreateCall4(CGM.getMemCpyFn(), 737193326Sed DestPtr, SrcPtr, 738193326Sed // TypeInfo.first describes size in bits. 739193326Sed llvm::ConstantInt::get(IntPtr, TypeInfo.first/8), 740198092Srdivacky llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 741193326Sed TypeInfo.second/8)); 742193326Sed} 743